) 中图学技术大荸学系 University of Science and Technology of China DEPARTMENT OF MATHEMATICS 第二步:第2行×a2 第行,i=3 12 13 a,n b, 12 0 2) (2 (2 (2) 2) 22 2n 00 3)(3) 33 3n 0 (2) 2) n2 (3) 3) 运算量:(m-2)*(1+n-1)=(m-2)n数 学 系 University of Science and Technology of China DEPARTMENT OF MATHEMATICS                 (3) (3) (3) 3 (3) 3 (3) 3 (3) 3 3 (2) 2 (2) 2 (2) 2 3 (2) 2 2 1 1 1 2 1 3 1 1 0 0 0 0 0 n n n n n n n a a b a a b a a a b a a a a b           运算量： (n-2)*(1+n-1)=(n-2)n 第二步： i i n a ai 2 , 3, , (2) 2 2 (2) 2 + =  − 第 行 第 行               (2) (2) (2) 2 (2) 2 (2) 2 (2) 22 11 12 1 1 0 0 n n n n n n a a b a a b a a a b        